This is not the first time that this has happened. In 2007 and last year, a large number of starfish gathered. Fishermen knew this situation in those years, and together with the local government, they killed a large number of breeding starfish. But now the effect is not satisfactory, and the situation that starfish gathered and endangered the ecological chain of the surrounding sea area has not been solved.

Starfish is called "sea locust". Once it strikes, it will inevitably damage seafood such as clams and oysters. In recent years, the starfish that broke out in Qingdao sea area are mainly starfish, which is a common cold-water species along the coast of the Yellow Sea in China. The optimum growth temperature is 15-20℃, and the upper limit of the optimum temperature is 25℃. They breed from 10 to the next year 1 month. Starfish is a greedy predatory creature, which has a great influence on the composition of benthos in the distribution area. It is an ecological enemy and an important enemy of mariculture industry.

For example, on March 5, 2002 1 year, according to Qingdao Marine Development Bureau, the starfish outbreaks in that year were mainly concentrated in the bottom-sowing area of oysters and clams in Jiaozhou Bay. According to rough statistics, the density of starfish reached an average of 50/m2, and the affected area was about100000 mu, which is expected to cause economic losses of about10000 million yuan. After the outbreak of starfish, local fishermen killed about 450 thousand Jin of starfish by artificial fishing. However, this year's situation has not improved compared with last year, and the reason is as long as it is affected by the following three reasons:

First, changes in the marine ecological environment.

The changes of various hydrological factors, such as nutrients, pH value and water temperature, provide suitable natural conditions for the growth and reproduction of starfish. Starfish have strong fecundity and extremely low survival rate. However, studies have shown that if the survival rate of starfish larvae is improved due to minor changes in the marine ecosystem, starfish will easily increase in large numbers when there are almost no natural enemies, and the starfish will move from deep sea to shallow sea, resulting in the rapid spread and outbreak of starfish in shellfish culture areas.

Second, it is the feeding habit of starfish.

Starfish have the habit of gathering in food-rich areas, mainly preying on bivalves, sea urchins, oysters and anemones. Jiaozhou Bay, as a shellfish culture area, its bottom-sown oysters and clams provide enough food for starfish, which provides an environmental basis for the massive reproduction of starfish. Some researchers have made investigations in shellfish culture areas, and there are often many starfish in the culture areas, but there are very few outside the culture areas. In 2007 and this year, almost all the starfish outbreaks in Qingdao occurred in aquaculture areas.

Third, the number of natural enemies has decreased.

Due to the influence of climate and other factors, the number of fish preying on starfish eggs and larvae in offshore waters has dropped sharply, which provides the possibility for the growth of starfish biomass.

Among these three reasons, the change of marine ecological environment is the main reason. Before, the temperature and sea water in nature were not suitable for the growth of starfish, but these two years have quietly changed to make the survival of starfish increase geometrically. But natural changes don't happen once a year, and it takes a long time to change. Facing the thorny problem of starfish flooding, all we can do is to increase the intensity of starfish fishing and minimize the harm.

Of course, some people wonder if we can kill starfish with our stomachs if we increase their intake. This idea is beautiful, but it is not easy to realize in reality. First, starfish grows and breeds too fast. Without control, it is absolutely impossible for human beings to keep up with its breeding speed only by natural consumption. In addition, starfish is troublesome for food processing, and its meat quality is not acceptable to the public. Again, the idea is beautiful, but the reality is very skinny.

From this, we can also see how important it is to protect our ocean and natural environment, which is the cornerstone of peaceful coexistence between human beings and other creatures. When their territory is invaded, it is the beginning of the conflict between the two sides for survival, and there is no sense of beauty.